Why Did Chevy Use a 2.0L Engine in the SS...
07-22-2010, 04:19 PM
#11
Senior Member
Join Date: 01-04-2010
Location: Imported from Detroit
Posts: 1,584
You can see why here..
http://198.208.187.166/us/powertrain...a/10car_us.htm
More specificaly
http://198.208.187.166/us/powertrain...c/10_LNF_n.doc
http://198.208.187.166/us/powertrain...a/10car_us.htm
More specificaly
http://198.208.187.166/us/powertrain...c/10_LNF_n.doc
07-22-2010, 05:30 PM
#12
Senior Member
Join Date: 01-10-2008
Location: NJ
Posts: 681
The GM 302 was built to compete at Bonneville with the Ford Boss 302 which set a record for horsepower at around 500 with the old fashioned fuel injectors in the late 60's early 70's. It was rare back then when the HP number was higher than the cubic inches. These days you 4 bangers pushing 1500 HP. Torque is a better comparison.
07-22-2010, 05:47 PM
#13
Senior Member
Join Date: 07-05-2008
Location: Akron Ohio
Posts: 5,464
Here is the GM press overveiw when it came out.
IMPROVING AN ALREADY STURDY DESIGN
A lot of development work went into this new version of the Ecotec; it wasn't simply a matter of plunking a turbo on the engine. Indeed, every major casting was redesigned to provide a heightened level of reliability, though the engine was originally designed for use in forced-induction applications.
As with the new supercharged Northstar engine in the new Cadillac XLR, the displacement of the Solstice GXP's is slightly smaller than the normally aspirated version. Both feature a reduced bore size to increase cylinder-wall thickness. The Ecotec Turbo's stroke is also reduced and features a beefy, forged-steel crankshaft for additional durability. Bore and stroke are 86x86 mm (3.38x3.38 inches) for a total displacement of 1,998 cc's or 122 ci.
The Ecotec 2.0-liter Turbo uses a stronger "Gen II" Ecotec engine block, which was developed with input from racing experience to support increased horsepower and torque. Cylinder-block bulkheads -- the areas where the main bearing caps are attached -- and the cylinder walls are enlarged for strength. Other areas of the engine were enhanced to reinforce the structure, and the water jacket is deeper for added cooling capacity and improved cylinder-bore roundness. This architecture is shared with the 2.4-liter Ecotec engine that debuted in the Pontiac Solstice roadster.
Its bottom end is also upgraded to handle the additional boost. In addition to the forged-steel crankshaft, the Ecotec Turbo also employs forged connecting rods and cast pistons. The pistons feature a dish shape that deflects injected fuel toward the spark plugs. They are cooled with a jet-spray of oil on their undersides that directs the oil into a cast-in channel inside the piston, further resisting detonation.
Additionally, the Ecotec 2.0-liter Turbo four benefits from variable valve timing and an intercooled, twin-scroll turbocharger system to provide boost. A dual-scroll design is used on the exhaust turbine and speeds up velocity and response, much in the same way a two-plane intake manifold performs the identical function. The result is a nearly lag-free system, one that gives the 2.0-liter four the feel of a much larger engine. Dual cam phasing complements the turbocharging by optimizing valve timing at lower rpm for best turbo response and quick engine build-up time. "There is virtually no lag with this system," says Ed Groff, assistant chief engineer, Ecotec 2.0-liter Turbo engine. "Throttle response is immediate. The engine acts like it has a larger displacement engine."
Its turbocharger provides up to approximately 20 pounds of boost. It is matched to the engine's displacement and performance objectives, and is supported by the air-to-air intercooling system, which reduces inlet temperature pf the turbo-compressed air by approximately 212 degrees (100 degrees C), enhancing performance because cooler air is denser.
DIRECT INJECTION
Perhaps the most innovative feature of the new turbocharged Solstice powerplant is the direct injection system. Essentially, the system locates the injector in the combustion chamber rather than in the intake manifold runner or intake port. This arrangement is similar in layout to a diesel powerplant, exposing the injector to the heat and pressure of the combustion event. Unlike a diesel, the Eccotec uses a conventional spark plug and otherwise operates as a normal four-cycle spark-ignition engine. The system is referred to as Spark Ignition Direct Injection (SIDI).
With fuel delivered directly to the combustion chamber to create a more complete burn of the air/fuel mixture, less fuel is required to produce the equivalent horsepower compared to a conventional port-injection system, particularly at normal cruising speeds. "Direct-injection technology works well with turbocharging and helps deliver a great balance of power and economy," says Groff. "The Ecotec 2.0-liter Turbo produces the power expected of a V-6, but in a smaller, more efficient pacckage -- and the driving response is simply terrific."
To accomodate the direct-injection system, the Ecotec 2.0-liter Turbo has a unique cylinder head and intake manifold. The cylinder head incorporates mounting locations for the fuel injectors -- which are typically mounted in the intake ports or intake manifold on port injection engines. A high-pressure fuel pump delivers fuel to a variable-pressure fuel rail. Fuel enters the combustion chamber through multihole fuel injectors. The fuel pump, fuel-rail pressure, fuel injection timing, and injection duration are controlled by the engine control module. In this way, fuel is metered and delivered in a finely atomized spray, which, during the intake stroke, is introduced into the chamber near the intake valves, in direct line of the spark plug. SIDI also permits a slightly higher compression ratio than if the fuel were delivered with conventional fuel injection and allows the mixture to be leaner at full power.
A high-pressure, returnless fuel system is employed for this application. It features a high-strength stainless steel fuel line that feeds a variable-pressure fuel rail. Direct injection requires higher fuel pressure than conventional fuel injected engines, and an engine-driven high-pressure fuel pump is used to supply up to 2,250 psi of pressure. This system regulates lower fuel pressure at idle -- approximately 752 psi and higher pressure at wide-open throttle. The cam-driven, high-pressure pump works in conjunction with a conventional fuel tank-mounted supply pump.
Apart from the mounting position of the fuel injectors, the cylinder head has conventional port and combustion designs, although both are optimized for direct injection and high boost pressures. Sodium-filled exhaust valves and stainless steel exhaust manifold are durable components designed to stand up to the high-performance capability of the engine.
A unique cylinder head, fuel system, pistons, intake manifold, and the dual-scroll turbocharger are the olny major ccomponents that differentiate the 2.0-liter Turbo from other members of the Ecotec engine family. Mobil 1 synthetic engine oil is added at the factory. Synthetic oil was selected for its friction-reducing capabilities and high-temperature performance.
DUAL CAM PHASING
The camshafts of the Ecotec 2.0-liter Turbo engine have phasers that support the continuously variable intake and exhaust valve timing. They also have cam position sensors, so that the engine control module can accurately control valve timing. The crankshaft and camshaft position sensors are digital. A new engine controller, specific to this powerplant, is used to sense and dictate its performance parameters.
Variable intake and exhaust timing works synergistically with both the gasoline direct injection and turbocharging systems. The variable engine timing enabled by cam phasing allows the combustion process to be optimized. Also, valve "overlap" at low rpm can be adjusted by the controller to increase the response of the turbocharger, providing a more immediate feeling of power.
ECOTEC ENGINE FAMILY
The Ecotec 2.0-liter Turbo is built on a global platform that was designed at the outset for a range of performance and combustion capabilities. Gen II blocks support the high-performance demands of the engines, but are merely a strengthened version of the original Ecotec architecture. The oil pump, for example, is the same as used in all other Ecotec engines. It was originally designed to support high-performance applications of future engines.
"This 2.0-liter Turbo is the pinnacle of Ecotec performance to date, with additional growth planned," says Groff. The groundwork for its capabilities was laid on the drawing table at the beginning of the Ecotec's development. Prior work and a far-thinking engine design continue to help GM respond to market demands around the globe more quickly and with greater accuracy."
This new Ecotec family member also features:
•Dual overhead camshafts (DOHC) and four valves per cylinder
•Twin counter-rotating balance shafts for operational smoothness
•"Drive by Wire" electronic throttle control
•Low friction, roller-finger follower valvetrain with hydraulic lash adjusters
•Low-maintenance chain-drive for the camshafts
•58X camshaft positioning
•Direct-mount accessories, which reduce or eliminate traditional sources of noise and vibration
•Full-circle transmission to reduce noise and vibration
•GM Oil Life System, which can reduce the frequency for oil changes
•Innovative cast-in oil filter housing, which eliminates the need to crawl under the vehicle to perform oil changes and eliminates throwaway oil filter cans that retain used oil.
•As with other engines in the Ecotec family, the 2.0-liter Turbo engine also has premium features designed to ensure smooth and quiet operation, including a polymer coating and skirt design for the pistons that reduce noise during cold starts. An automatic hydraulic tensioner also is used to maintain optimal tension on the timing chain, which reduces noise and vibration.
IMPROVING AN ALREADY STURDY DESIGN
A lot of development work went into this new version of the Ecotec; it wasn't simply a matter of plunking a turbo on the engine. Indeed, every major casting was redesigned to provide a heightened level of reliability, though the engine was originally designed for use in forced-induction applications.
As with the new supercharged Northstar engine in the new Cadillac XLR, the displacement of the Solstice GXP's is slightly smaller than the normally aspirated version. Both feature a reduced bore size to increase cylinder-wall thickness. The Ecotec Turbo's stroke is also reduced and features a beefy, forged-steel crankshaft for additional durability. Bore and stroke are 86x86 mm (3.38x3.38 inches) for a total displacement of 1,998 cc's or 122 ci.
The Ecotec 2.0-liter Turbo uses a stronger "Gen II" Ecotec engine block, which was developed with input from racing experience to support increased horsepower and torque. Cylinder-block bulkheads -- the areas where the main bearing caps are attached -- and the cylinder walls are enlarged for strength. Other areas of the engine were enhanced to reinforce the structure, and the water jacket is deeper for added cooling capacity and improved cylinder-bore roundness. This architecture is shared with the 2.4-liter Ecotec engine that debuted in the Pontiac Solstice roadster.
Its bottom end is also upgraded to handle the additional boost. In addition to the forged-steel crankshaft, the Ecotec Turbo also employs forged connecting rods and cast pistons. The pistons feature a dish shape that deflects injected fuel toward the spark plugs. They are cooled with a jet-spray of oil on their undersides that directs the oil into a cast-in channel inside the piston, further resisting detonation.
Additionally, the Ecotec 2.0-liter Turbo four benefits from variable valve timing and an intercooled, twin-scroll turbocharger system to provide boost. A dual-scroll design is used on the exhaust turbine and speeds up velocity and response, much in the same way a two-plane intake manifold performs the identical function. The result is a nearly lag-free system, one that gives the 2.0-liter four the feel of a much larger engine. Dual cam phasing complements the turbocharging by optimizing valve timing at lower rpm for best turbo response and quick engine build-up time. "There is virtually no lag with this system," says Ed Groff, assistant chief engineer, Ecotec 2.0-liter Turbo engine. "Throttle response is immediate. The engine acts like it has a larger displacement engine."
Its turbocharger provides up to approximately 20 pounds of boost. It is matched to the engine's displacement and performance objectives, and is supported by the air-to-air intercooling system, which reduces inlet temperature pf the turbo-compressed air by approximately 212 degrees (100 degrees C), enhancing performance because cooler air is denser.
DIRECT INJECTION
Perhaps the most innovative feature of the new turbocharged Solstice powerplant is the direct injection system. Essentially, the system locates the injector in the combustion chamber rather than in the intake manifold runner or intake port. This arrangement is similar in layout to a diesel powerplant, exposing the injector to the heat and pressure of the combustion event. Unlike a diesel, the Eccotec uses a conventional spark plug and otherwise operates as a normal four-cycle spark-ignition engine. The system is referred to as Spark Ignition Direct Injection (SIDI).
With fuel delivered directly to the combustion chamber to create a more complete burn of the air/fuel mixture, less fuel is required to produce the equivalent horsepower compared to a conventional port-injection system, particularly at normal cruising speeds. "Direct-injection technology works well with turbocharging and helps deliver a great balance of power and economy," says Groff. "The Ecotec 2.0-liter Turbo produces the power expected of a V-6, but in a smaller, more efficient pacckage -- and the driving response is simply terrific."
To accomodate the direct-injection system, the Ecotec 2.0-liter Turbo has a unique cylinder head and intake manifold. The cylinder head incorporates mounting locations for the fuel injectors -- which are typically mounted in the intake ports or intake manifold on port injection engines. A high-pressure fuel pump delivers fuel to a variable-pressure fuel rail. Fuel enters the combustion chamber through multihole fuel injectors. The fuel pump, fuel-rail pressure, fuel injection timing, and injection duration are controlled by the engine control module. In this way, fuel is metered and delivered in a finely atomized spray, which, during the intake stroke, is introduced into the chamber near the intake valves, in direct line of the spark plug. SIDI also permits a slightly higher compression ratio than if the fuel were delivered with conventional fuel injection and allows the mixture to be leaner at full power.
A high-pressure, returnless fuel system is employed for this application. It features a high-strength stainless steel fuel line that feeds a variable-pressure fuel rail. Direct injection requires higher fuel pressure than conventional fuel injected engines, and an engine-driven high-pressure fuel pump is used to supply up to 2,250 psi of pressure. This system regulates lower fuel pressure at idle -- approximately 752 psi and higher pressure at wide-open throttle. The cam-driven, high-pressure pump works in conjunction with a conventional fuel tank-mounted supply pump.
Apart from the mounting position of the fuel injectors, the cylinder head has conventional port and combustion designs, although both are optimized for direct injection and high boost pressures. Sodium-filled exhaust valves and stainless steel exhaust manifold are durable components designed to stand up to the high-performance capability of the engine.
A unique cylinder head, fuel system, pistons, intake manifold, and the dual-scroll turbocharger are the olny major ccomponents that differentiate the 2.0-liter Turbo from other members of the Ecotec engine family. Mobil 1 synthetic engine oil is added at the factory. Synthetic oil was selected for its friction-reducing capabilities and high-temperature performance.
DUAL CAM PHASING
The camshafts of the Ecotec 2.0-liter Turbo engine have phasers that support the continuously variable intake and exhaust valve timing. They also have cam position sensors, so that the engine control module can accurately control valve timing. The crankshaft and camshaft position sensors are digital. A new engine controller, specific to this powerplant, is used to sense and dictate its performance parameters.
Variable intake and exhaust timing works synergistically with both the gasoline direct injection and turbocharging systems. The variable engine timing enabled by cam phasing allows the combustion process to be optimized. Also, valve "overlap" at low rpm can be adjusted by the controller to increase the response of the turbocharger, providing a more immediate feeling of power.
ECOTEC ENGINE FAMILY
The Ecotec 2.0-liter Turbo is built on a global platform that was designed at the outset for a range of performance and combustion capabilities. Gen II blocks support the high-performance demands of the engines, but are merely a strengthened version of the original Ecotec architecture. The oil pump, for example, is the same as used in all other Ecotec engines. It was originally designed to support high-performance applications of future engines.
"This 2.0-liter Turbo is the pinnacle of Ecotec performance to date, with additional growth planned," says Groff. The groundwork for its capabilities was laid on the drawing table at the beginning of the Ecotec's development. Prior work and a far-thinking engine design continue to help GM respond to market demands around the globe more quickly and with greater accuracy."
This new Ecotec family member also features:
•Dual overhead camshafts (DOHC) and four valves per cylinder
•Twin counter-rotating balance shafts for operational smoothness
•"Drive by Wire" electronic throttle control
•Low friction, roller-finger follower valvetrain with hydraulic lash adjusters
•Low-maintenance chain-drive for the camshafts
•58X camshaft positioning
•Direct-mount accessories, which reduce or eliminate traditional sources of noise and vibration
•Full-circle transmission to reduce noise and vibration
•GM Oil Life System, which can reduce the frequency for oil changes
•Innovative cast-in oil filter housing, which eliminates the need to crawl under the vehicle to perform oil changes and eliminates throwaway oil filter cans that retain used oil.
•As with other engines in the Ecotec family, the 2.0-liter Turbo engine also has premium features designed to ensure smooth and quiet operation, including a polymer coating and skirt design for the pistons that reduce noise during cold starts. An automatic hydraulic tensioner also is used to maintain optimal tension on the timing chain, which reduces noise and vibration.
07-22-2010, 07:51 PM
#16
Member
Thread Starter
Join Date: 07-10-2010
Location: SoCal
Posts: 56
You can see why here..
http://198.208.187.166/us/powertrain...a/10car_us.htm
More specificaly
http://198.208.187.166/us/powertrain...c/10_LNF_n.doc
http://198.208.187.166/us/powertrain...a/10car_us.htm
More specificaly
http://198.208.187.166/us/powertrain...c/10_LNF_n.doc
07-22-2010, 07:53 PM
#17
Member
Thread Starter
Join Date: 07-10-2010
Location: SoCal
Posts: 56
Here is the GM press overveiw when it came out.
IMPROVING AN ALREADY STURDY DESIGN
A lot of development work went into this new version of the Ecotec; it wasn't simply a matter of plunking a turbo on the engine. Indeed, every major casting was redesigned to provide a heightened level of reliability, though the engine was originally designed for use in forced-induction applications.
As with the new supercharged Northstar engine in the new Cadillac XLR, the displacement of the Solstice GXP's is slightly smaller than the normally aspirated version. Both feature a reduced bore size to increase cylinder-wall thickness. The Ecotec Turbo's stroke is also reduced and features a beefy, forged-steel crankshaft for additional durability. Bore and stroke are 86x86 mm (3.38x3.38 inches) for a total displacement of 1,998 cc's or 122 ci.
The Ecotec 2.0-liter Turbo uses a stronger "Gen II" Ecotec engine block, which was developed with input from racing experience to support increased horsepower and torque. Cylinder-block bulkheads -- the areas where the main bearing caps are attached -- and the cylinder walls are enlarged for strength. Other areas of the engine were enhanced to reinforce the structure, and the water jacket is deeper for added cooling capacity and improved cylinder-bore roundness. This architecture is shared with the 2.4-liter Ecotec engine that debuted in the Pontiac Solstice roadster.
Its bottom end is also upgraded to handle the additional boost. In addition to the forged-steel crankshaft, the Ecotec Turbo also employs forged connecting rods and cast pistons. The pistons feature a dish shape that deflects injected fuel toward the spark plugs. They are cooled with a jet-spray of oil on their undersides that directs the oil into a cast-in channel inside the piston, further resisting detonation.
Additionally, the Ecotec 2.0-liter Turbo four benefits from variable valve timing and an intercooled, twin-scroll turbocharger system to provide boost. A dual-scroll design is used on the exhaust turbine and speeds up velocity and response, much in the same way a two-plane intake manifold performs the identical function. The result is a nearly lag-free system, one that gives the 2.0-liter four the feel of a much larger engine. Dual cam phasing complements the turbocharging by optimizing valve timing at lower rpm for best turbo response and quick engine build-up time. "There is virtually no lag with this system," says Ed Groff, assistant chief engineer, Ecotec 2.0-liter Turbo engine. "Throttle response is immediate. The engine acts like it has a larger displacement engine."
Its turbocharger provides up to approximately 20 pounds of boost. It is matched to the engine's displacement and performance objectives, and is supported by the air-to-air intercooling system, which reduces inlet temperature pf the turbo-compressed air by approximately 212 degrees (100 degrees C), enhancing performance because cooler air is denser.
DIRECT INJECTION
Perhaps the most innovative feature of the new turbocharged Solstice powerplant is the direct injection system. Essentially, the system locates the injector in the combustion chamber rather than in the intake manifold runner or intake port. This arrangement is similar in layout to a diesel powerplant, exposing the injector to the heat and pressure of the combustion event. Unlike a diesel, the Eccotec uses a conventional spark plug and otherwise operates as a normal four-cycle spark-ignition engine. The system is referred to as Spark Ignition Direct Injection (SIDI).
With fuel delivered directly to the combustion chamber to create a more complete burn of the air/fuel mixture, less fuel is required to produce the equivalent horsepower compared to a conventional port-injection system, particularly at normal cruising speeds. "Direct-injection technology works well with turbocharging and helps deliver a great balance of power and economy," says Groff. "The Ecotec 2.0-liter Turbo produces the power expected of a V-6, but in a smaller, more efficient pacckage -- and the driving response is simply terrific."
To accomodate the direct-injection system, the Ecotec 2.0-liter Turbo has a unique cylinder head and intake manifold. The cylinder head incorporates mounting locations for the fuel injectors -- which are typically mounted in the intake ports or intake manifold on port injection engines. A high-pressure fuel pump delivers fuel to a variable-pressure fuel rail. Fuel enters the combustion chamber through multihole fuel injectors. The fuel pump, fuel-rail pressure, fuel injection timing, and injection duration are controlled by the engine control module. In this way, fuel is metered and delivered in a finely atomized spray, which, during the intake stroke, is introduced into the chamber near the intake valves, in direct line of the spark plug. SIDI also permits a slightly higher compression ratio than if the fuel were delivered with conventional fuel injection and allows the mixture to be leaner at full power.
A high-pressure, returnless fuel system is employed for this application. It features a high-strength stainless steel fuel line that feeds a variable-pressure fuel rail. Direct injection requires higher fuel pressure than conventional fuel injected engines, and an engine-driven high-pressure fuel pump is used to supply up to 2,250 psi of pressure. This system regulates lower fuel pressure at idle -- approximately 752 psi and higher pressure at wide-open throttle. The cam-driven, high-pressure pump works in conjunction with a conventional fuel tank-mounted supply pump.
Apart from the mounting position of the fuel injectors, the cylinder head has conventional port and combustion designs, although both are optimized for direct injection and high boost pressures. Sodium-filled exhaust valves and stainless steel exhaust manifold are durable components designed to stand up to the high-performance capability of the engine.
A unique cylinder head, fuel system, pistons, intake manifold, and the dual-scroll turbocharger are the olny major ccomponents that differentiate the 2.0-liter Turbo from other members of the Ecotec engine family. Mobil 1 synthetic engine oil is added at the factory. Synthetic oil was selected for its friction-reducing capabilities and high-temperature performance.
DUAL CAM PHASING
The camshafts of the Ecotec 2.0-liter Turbo engine have phasers that support the continuously variable intake and exhaust valve timing. They also have cam position sensors, so that the engine control module can accurately control valve timing. The crankshaft and camshaft position sensors are digital. A new engine controller, specific to this powerplant, is used to sense and dictate its performance parameters.
Variable intake and exhaust timing works synergistically with both the gasoline direct injection and turbocharging systems. The variable engine timing enabled by cam phasing allows the combustion process to be optimized. Also, valve "overlap" at low rpm can be adjusted by the controller to increase the response of the turbocharger, providing a more immediate feeling of power.
ECOTEC ENGINE FAMILY
The Ecotec 2.0-liter Turbo is built on a global platform that was designed at the outset for a range of performance and combustion capabilities. Gen II blocks support the high-performance demands of the engines, but are merely a strengthened version of the original Ecotec architecture. The oil pump, for example, is the same as used in all other Ecotec engines. It was originally designed to support high-performance applications of future engines.
"This 2.0-liter Turbo is the pinnacle of Ecotec performance to date, with additional growth planned," says Groff. The groundwork for its capabilities was laid on the drawing table at the beginning of the Ecotec's development. Prior work and a far-thinking engine design continue to help GM respond to market demands around the globe more quickly and with greater accuracy."
This new Ecotec family member also features:
•Dual overhead camshafts (DOHC) and four valves per cylinder
•Twin counter-rotating balance shafts for operational smoothness
•"Drive by Wire" electronic throttle control
•Low friction, roller-finger follower valvetrain with hydraulic lash adjusters
•Low-maintenance chain-drive for the camshafts
•58X camshaft positioning
•Direct-mount accessories, which reduce or eliminate traditional sources of noise and vibration
•Full-circle transmission to reduce noise and vibration
•GM Oil Life System, which can reduce the frequency for oil changes
•Innovative cast-in oil filter housing, which eliminates the need to crawl under the vehicle to perform oil changes and eliminates throwaway oil filter cans that retain used oil.
•As with other engines in the Ecotec family, the 2.0-liter Turbo engine also has premium features designed to ensure smooth and quiet operation, including a polymer coating and skirt design for the pistons that reduce noise during cold starts. An automatic hydraulic tensioner also is used to maintain optimal tension on the timing chain, which reduces noise and vibration.
IMPROVING AN ALREADY STURDY DESIGN
A lot of development work went into this new version of the Ecotec; it wasn't simply a matter of plunking a turbo on the engine. Indeed, every major casting was redesigned to provide a heightened level of reliability, though the engine was originally designed for use in forced-induction applications.
As with the new supercharged Northstar engine in the new Cadillac XLR, the displacement of the Solstice GXP's is slightly smaller than the normally aspirated version. Both feature a reduced bore size to increase cylinder-wall thickness. The Ecotec Turbo's stroke is also reduced and features a beefy, forged-steel crankshaft for additional durability. Bore and stroke are 86x86 mm (3.38x3.38 inches) for a total displacement of 1,998 cc's or 122 ci.
The Ecotec 2.0-liter Turbo uses a stronger "Gen II" Ecotec engine block, which was developed with input from racing experience to support increased horsepower and torque. Cylinder-block bulkheads -- the areas where the main bearing caps are attached -- and the cylinder walls are enlarged for strength. Other areas of the engine were enhanced to reinforce the structure, and the water jacket is deeper for added cooling capacity and improved cylinder-bore roundness. This architecture is shared with the 2.4-liter Ecotec engine that debuted in the Pontiac Solstice roadster.
Its bottom end is also upgraded to handle the additional boost. In addition to the forged-steel crankshaft, the Ecotec Turbo also employs forged connecting rods and cast pistons. The pistons feature a dish shape that deflects injected fuel toward the spark plugs. They are cooled with a jet-spray of oil on their undersides that directs the oil into a cast-in channel inside the piston, further resisting detonation.
Additionally, the Ecotec 2.0-liter Turbo four benefits from variable valve timing and an intercooled, twin-scroll turbocharger system to provide boost. A dual-scroll design is used on the exhaust turbine and speeds up velocity and response, much in the same way a two-plane intake manifold performs the identical function. The result is a nearly lag-free system, one that gives the 2.0-liter four the feel of a much larger engine. Dual cam phasing complements the turbocharging by optimizing valve timing at lower rpm for best turbo response and quick engine build-up time. "There is virtually no lag with this system," says Ed Groff, assistant chief engineer, Ecotec 2.0-liter Turbo engine. "Throttle response is immediate. The engine acts like it has a larger displacement engine."
Its turbocharger provides up to approximately 20 pounds of boost. It is matched to the engine's displacement and performance objectives, and is supported by the air-to-air intercooling system, which reduces inlet temperature pf the turbo-compressed air by approximately 212 degrees (100 degrees C), enhancing performance because cooler air is denser.
DIRECT INJECTION
Perhaps the most innovative feature of the new turbocharged Solstice powerplant is the direct injection system. Essentially, the system locates the injector in the combustion chamber rather than in the intake manifold runner or intake port. This arrangement is similar in layout to a diesel powerplant, exposing the injector to the heat and pressure of the combustion event. Unlike a diesel, the Eccotec uses a conventional spark plug and otherwise operates as a normal four-cycle spark-ignition engine. The system is referred to as Spark Ignition Direct Injection (SIDI).
With fuel delivered directly to the combustion chamber to create a more complete burn of the air/fuel mixture, less fuel is required to produce the equivalent horsepower compared to a conventional port-injection system, particularly at normal cruising speeds. "Direct-injection technology works well with turbocharging and helps deliver a great balance of power and economy," says Groff. "The Ecotec 2.0-liter Turbo produces the power expected of a V-6, but in a smaller, more efficient pacckage -- and the driving response is simply terrific."
To accomodate the direct-injection system, the Ecotec 2.0-liter Turbo has a unique cylinder head and intake manifold. The cylinder head incorporates mounting locations for the fuel injectors -- which are typically mounted in the intake ports or intake manifold on port injection engines. A high-pressure fuel pump delivers fuel to a variable-pressure fuel rail. Fuel enters the combustion chamber through multihole fuel injectors. The fuel pump, fuel-rail pressure, fuel injection timing, and injection duration are controlled by the engine control module. In this way, fuel is metered and delivered in a finely atomized spray, which, during the intake stroke, is introduced into the chamber near the intake valves, in direct line of the spark plug. SIDI also permits a slightly higher compression ratio than if the fuel were delivered with conventional fuel injection and allows the mixture to be leaner at full power.
A high-pressure, returnless fuel system is employed for this application. It features a high-strength stainless steel fuel line that feeds a variable-pressure fuel rail. Direct injection requires higher fuel pressure than conventional fuel injected engines, and an engine-driven high-pressure fuel pump is used to supply up to 2,250 psi of pressure. This system regulates lower fuel pressure at idle -- approximately 752 psi and higher pressure at wide-open throttle. The cam-driven, high-pressure pump works in conjunction with a conventional fuel tank-mounted supply pump.
Apart from the mounting position of the fuel injectors, the cylinder head has conventional port and combustion designs, although both are optimized for direct injection and high boost pressures. Sodium-filled exhaust valves and stainless steel exhaust manifold are durable components designed to stand up to the high-performance capability of the engine.
A unique cylinder head, fuel system, pistons, intake manifold, and the dual-scroll turbocharger are the olny major ccomponents that differentiate the 2.0-liter Turbo from other members of the Ecotec engine family. Mobil 1 synthetic engine oil is added at the factory. Synthetic oil was selected for its friction-reducing capabilities and high-temperature performance.
DUAL CAM PHASING
The camshafts of the Ecotec 2.0-liter Turbo engine have phasers that support the continuously variable intake and exhaust valve timing. They also have cam position sensors, so that the engine control module can accurately control valve timing. The crankshaft and camshaft position sensors are digital. A new engine controller, specific to this powerplant, is used to sense and dictate its performance parameters.
Variable intake and exhaust timing works synergistically with both the gasoline direct injection and turbocharging systems. The variable engine timing enabled by cam phasing allows the combustion process to be optimized. Also, valve "overlap" at low rpm can be adjusted by the controller to increase the response of the turbocharger, providing a more immediate feeling of power.
ECOTEC ENGINE FAMILY
The Ecotec 2.0-liter Turbo is built on a global platform that was designed at the outset for a range of performance and combustion capabilities. Gen II blocks support the high-performance demands of the engines, but are merely a strengthened version of the original Ecotec architecture. The oil pump, for example, is the same as used in all other Ecotec engines. It was originally designed to support high-performance applications of future engines.
"This 2.0-liter Turbo is the pinnacle of Ecotec performance to date, with additional growth planned," says Groff. The groundwork for its capabilities was laid on the drawing table at the beginning of the Ecotec's development. Prior work and a far-thinking engine design continue to help GM respond to market demands around the globe more quickly and with greater accuracy."
This new Ecotec family member also features:
•Dual overhead camshafts (DOHC) and four valves per cylinder
•Twin counter-rotating balance shafts for operational smoothness
•"Drive by Wire" electronic throttle control
•Low friction, roller-finger follower valvetrain with hydraulic lash adjusters
•Low-maintenance chain-drive for the camshafts
•58X camshaft positioning
•Direct-mount accessories, which reduce or eliminate traditional sources of noise and vibration
•Full-circle transmission to reduce noise and vibration
•GM Oil Life System, which can reduce the frequency for oil changes
•Innovative cast-in oil filter housing, which eliminates the need to crawl under the vehicle to perform oil changes and eliminates throwaway oil filter cans that retain used oil.
•As with other engines in the Ecotec family, the 2.0-liter Turbo engine also has premium features designed to ensure smooth and quiet operation, including a polymer coating and skirt design for the pistons that reduce noise during cold starts. An automatic hydraulic tensioner also is used to maintain optimal tension on the timing chain, which reduces noise and vibration.
07-22-2010, 10:34 PM
#20
Platinum Member
Join Date: 01-09-2007
Location: SE USA
Posts: 15,975
Also why Stroker motors can't rev to the sky..
Some people say Chevy put the crank in a 350 block but since 1967 was the first year for 350's and 302's and both used the 327 block it is better to say they used a 327 block. A 302, 327 and 350 block are exactly the same except for the number of main bolts which would depend on the application and the year. The 1969 302's had 4 bolt mains. The 1967 and 1968 302's did not have 4 bolt mains. They were in fact 2 bolt main blocks used in '67 and '68 302's.